Heat loss calc: basement infiltration?

woobagooba

Folks

As part of my GB142 repair / replace adventure, I'm doing a heat loss calc for the premises ... first for the entire house, then per room.

Chapter 2 of Siegenthaler's "Modern Hydronic ..." is my guide. The basement conduction calc, which breaks the basement walls into three parts, makes sense. I am not at all sure how to account for basement infiltration (the example uses a slab). Any guidance on this greatly appreciated. Thank you.

Jamie Hall

What type of construction is the basement? Poured concrete? Mortared stone? Dry laid stone? Concrete block? And how well -- if at all -- are the sills sealed to the top of the foundation walls? That all makes a difference... if the sills are well sealed to the tops of poured concrete or well made block, and the windows are tight, you might get away with 2 to 4 air changes per hour. On the other hand, dry laid stone... oy. Anyone's guess.

STEVEusaPA

City/State? How many 100's of btu's in gas did you use in the last 12 months?
Just trying to do a quick calc for you.

woobagooba

Basement is field-stone with about 1'of sill above grade. No insulation. Premises is in Eastern MA area. No idea what was the prior owner's gas consumption last year.

I am pretty far along with whole house heat calc (Excel spreadsheet so I can what-if the improvement plans). Just not clear how to handle the basement infiltration.

Jamie Hall

Field stone... older? Mortared, more or less, probably no adequate sill seal. I'd be looking at 5 to 10 air changes per hour.

unclejohn

Also you need to plug in the landing strip lights.